Evacuation means for an open end spinning device

ABSTRACT

The spinning device has a cover disposed over the rotor to project into the opening of the rotor with a clearance therebetween to permit evacuation of the rotor upon spinning. The cover can be provided with a groove or vane to facilitate the evacuation of the rotor or the rotor can be provided with a flange or blades to facilitate evacuation.

United States Patent I I I Inventors Appl. No.

Filed Patented Assignee Priority Adolf Schiltknecht;

Max Grai', both of Winterthur, Switzerland 761,742

Sept. 23, I968 June I5, 1971 Rieter Machine Works, Ltd.

Winterthur, Switzerland Sept. 27, 1967 Switzerland EVACUATION MEANS FOR AN OPEN END SPINNING DEVICE 14 Claims, 11 Drawing Figs.

U.S. Cl Int. Cl.......

l 13,5s4,4s2

[50] Field of Search 57/58.89-

[56] References Cited UNITED STATES PATENTS 3.361099 2/1968 Kubony et al S7/58.89 3,447,298 6/1969 Collins 57/5889 Primary ExaminerDonald E. Watkins Attorney- Kenyon & Kenyon Reilly Carr & Chapin ABSTRACT: The spinning device has a cover disposed over the rotor to project into the opening of the rotor with a clearance therebetween to permit evacuation of the rotor upon spinning. The cover can be provided with a groove or vane to facilitate the evacuation of the rotor or the rotor can be provided with a flange or blades to facilitate evacuation.

EVACUATION MEANS FOR AN OPEN END SPINNING DEVICE This invention relates to evacuation means for a spinning device for open end spinning of yarns.

In open end spinning devices, rotors have been provided with perforated fiber collecting surfaces or with perforations for ventilation in close vicinity of the fiber collecting surface in order to create the vacuum needed. However, the perforations even if arranged outside the area of actual yarn formation, have been exposed to the danger of clogging and, thus, such has to be taken into account, especially since, during startup, stopoff and piecing operations, yarn fragments or fiber tufts could be sucked into the perforations and thus could cause disturbances. Elimination of this disadvantage has been attempted by the use of external suction devices whereby a clearance between a rotor rim and a stationary cover of the spinning device has been provided through which an evacuating air stream has been generated by the external vacuum. A disadvantage of this arrangement, however, is the necessity of creating the vacuum needed for regular operations by means of a separate fan. Further, as the air fiow requires changes with production rate and rotor speed, the fan speed would require adaptation to the rotor speed and thus would further complicate the design correspondingly.

Accordingly, it is an object of the invention to provide a device incorporating the advantages of rotor perforations and external suction for evacuating an open end spinning device while avoiding the disadvantages of the two suction methods.

It is another object of the invention to evacuate a rotor of an open end spinning device without the use of independently operated suction devices.

It is another object of the invention to evacuate a rotor of an open end spinning device in a simple efficient manner.

It is another object of the invention to evacuate a rotor from a point spaced from the fiber collecting surface as well as from the fiber feed path.

Briefly, the invention provides a rotor of an open end spinning device having a fiber collecting surface and an open rim with a stationary cover which faces the open rim. The cover is disposed to project into the open rim with a slight clearance to create a path for the flow of air from a point of high pressure within the rotor to a point of low pressure out side the rotor. The difference in pressure is created, in one embodiment, by extending an annular flange on the rotor upwardly about the cover and by incorporating a helical groove or rib on the cover. In another embodiment, the pressure differential is caused by extending an annular flange on the rotor outwardly about the cover or by placing blades on the outside of the rotor. In still another embodiment, an annular flange on the rotor extending upwardly is conically shaped while the cover is provided with a complementary depending conical surface spaced slightly from the rotor flange. The conical surface is also provided with a helical groove facing the rotor flange.

The cover which is positioned in spaced relation to the rotor is of a cylindrical shape and is stationary with respect to the rotor. However, the cover can also be made of a conical shape and can be adjustable in height with respect to the rotor rim so as to vary the clearance between the rotor and cover to vary the volume of air flow therebetween and vacuum inside the rotor.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIGS. 1 to 3 respectively illustrate cross-sectional views of conventional rotors of prior open end spinning devices;

FIG. 4 illustrates a cross-sectional view of a rotor of an open end spinning device incorporating an evacuation means of the invention;

FIG. 5 illustrates a cross-sectional view of a modified evacuation means according to the invention;

FIG. 6 illustrates a fragmentary view of a cover according to the invention in relation to a rotor according to the invention;

FIG. 7 illustrates a cross-sectional view of another modified evacuation means according to the invention utilizing a flange on the rotor;

FIG. 8 illustrates a view similar to FIG. 7 ofa modified rotor utilizing blades on the rotor according to the invention;

FIG. 9 illustrates a cross-sectional view of a rotor and cover having complementary conical walls according to the invention; and

FIGS. 10 and 11 respectively illustrate views similar to FIG. 8 ofa modified rotor having blades according to the invention.

Referring to FIG. I, the rotor of an open end spinning device has usually been provided with an internal fiber collecting surface 2, usually shaped as a groove, on the bottom 3 of which fibers 5 after entering through an overhead duct 4 form a fiber ring 6. The fiber ring 6 is pulled ofi centrally in the form of a yarn 7 and is taken up by a winding device below the rotor 1. In some instances, ventilation perforations 8 are arranged in the groove bottom 3 to provide for evacuation of the rotor interior.

Referring to FIG. 2, holes 9 are also sometimes placed towards the center, outside the groove bottom which in this instance is provided with a larger base 10.

Referring to FIG. 3, in other instances a rotor 11 has been evacuated by external suction means. In such instances, a gap 14 is formed between a stationary cover 12 and the open rim 13 of the rotor 11 through which gap the vacuum in a surrounding housing 15 which is generated by a vacuum source outside the device via a connection duct 16 evacuates the inside of the rotor 11.

These various structures of FIGS. 1 to 3 represent the state of the prior art with the major disadvantages mentioned above.

Referring to FIG. 4, the open end spinning device of the invention includes a rotor 17 having an upstanding annular flange or collar 18 extending from the rim and a cover 19 which is mounted over the rotor 17. The rotor 17 is driven from a shaft 38 and has an internal fiber collecting surface 39 in the form of an annular groove as is known. The cover 19 is of a substantially T-shaped cross section and has a cylindrical stern portion which projects into the collar 18 in spaced relation to define an annular clearance or gap 20 therebetween. In addition, a helical groove 21 is formed in the stem portion of the cover 19 within the area which protrudes into the collar 18 in facing relation to the collar 18 and which extends upwardly beyond the plane of the collar 18. The groove 21 is directed in the same direction as the sense of rotation of the rotor 17 as indicated by the arrows.

In operation, as the rotor I7 is caused to rotate, the fiber collecting surface 39 is continuously evacuated by the combined action of the rotor collar 18 and the helical groove 21 in the cover 19. The flow path of the air which is evacuated follows a course along the groove 21 upwardly out of the rotor 17 to the exterior of the rotor 17 due to the lower pressure existing immediately outside the rotor 17.

Referring to FIG. 5, wherein like reference characters refer to like parts described above, the rotor 17 has an upstanding annular flange or collar 23 which has an internal conical wall which faces a complementary shaped conical wall on the stem portion of the cover 19. In addition, the stem portion of the cover 19 includes a helical evacuation groove 22 which extends upwardly above the collar 23 and functions as above to evacuate the fiber collecting surface 39. The rotor 17 is further rotatably mounted via the shaft 38 in a surrounding housing 24. Further, the cover 19 is supported at the outer rim over the rotor 17 by an intermediate ring 25 which is threadably mounted in the upper end of the housing 24. Thus, by suitably turning the intermediate ring 25 with respect to the housing 24, the axial position of the cover 19 with respect to the rotor 17 and, thus, the width of the clearance between the stem portion of the cover 19 and the collar 23 of the rotor 17 can be varied. This allows the volume of air and the vacuum within the rotor to be varied or adjusted to operating conditions. The evacuated air from the rotor 17 is further exhausted through an outlet pipe 40 in the wall of the housing 24 in the direction indicated by the arrow.

Referring to FIG. 6, the stem portion of the cover 26 within the collar 23 of the rotor, instead of being provided with a groove, can be provided with a helical rib 27 which acts as a guide blade to evacuate air from the rotor. In such a case, the clearance between the stem portion of the cover 26 and the collar 23 is slightly greater to accommodate the height of the rib 27.

Referring to FIG. 7, instead of providing the cover 19 with an evacuating groove and the rotor 17 with an upstanding collar, the rotor 17 can be provided with an outwardly extending radial flange 28 on the open rim to create the evacuation action.

Referring to FIG. 8, instead of using a radial flange, a plurality of blades 29 are arranged radially, as are fan blades, or inclined backwardly or forwardly on the exterior of the rotor 17 to create a sufficient differential in pressure within and without the rotor 17 to evacuate the fiber collecting surface 39.

Referring to FIG. 9, wherein like reference characters have been used to indicate like parts above, the cover 30 is provided with a conical surface 31 parallel to the exterior surface of a conically shaped collar 32 on the rim of the rotor 17. In addition, a helical groove 33, as above, is formed in the conical surface 31 in facing relation to the collar 32. The collar 32 thus projects into the cover 30 in spaced relation to cause the evacuated air to flow in the direction indicated by the arrows.

As shown, the cover 30 is threadably mounted in an intermediate ring 41 which is mounted on the housing 26 containing the rotor 17. The cover is thus adjustable axially of the rotor 17 to vary the clearance between the conical surface 31 and collar 32.

Referring to FIG. 10, the rotor 17 is provided with exterior blades 34 along the largest diameter to create the evacuation pressure. The housing 42 containing the rotor 17 is further recessed in the sidewalls to accommodate the blades 34 and the outlet pipe 43 is disposed in the plane of the blades 34.

Further, the cover M is similar to cover 30 above in that such contains a conical surface 45 parallel to a conical rim of the rotor 17. The rotor rim is thus disposed to project into the cover 44. Also, the cover 44 is supported on the housing 42 to enclose the rotor 17 therein.

Referring finally to FIG. 11, the rotor 37 is provided with exterior blades 35 on a radial flange 36. The blades 35 project upwardly and are disposed about the stem portion of the cover to direct an air flow through the outlet pipe 40 out of the housing 24. The stem portion of the cover 19 further protrudes slightly into the open end of the rotor 37. The rotor 37, in this case, acts in the manner of a ring fan, for example, a side duct compressor fan.

What we claim is:

l. The combination of a rotor of an open end spinning device having an open end on the side facing a fiber feed point and an internal fiber collecting surface, a cover over said open end of said rotor, and means for evacuating said fiber collecting surface, said means being mounted on one of said rotor and said cover and spaced from said fiber collecting surface and a fiber feed path between said feed point and said fiber collecting surface to evacuate air from within said rotor through a path between said rotor and said cover into a space surrounding said rotor.

2. The combination as set forth in clam 1 wherein said means includes a collar on said rotor about said open end extending upwardly therefrom, and a stem portion on said cover projecting into said collar in spaced relation thereto to define an annular clearance.

3. The combination as set forth in claim 2 wherein said stem portion has a conical wall thereon and said collar has a complementary conical wall thereon in facing relation to said stern portion.

4. The combination as set forth In claim 3 wherein said cover is adjustably mounted axially of said rotor to vary the clearance between said stem portion and said collar.

5. The combination as set forth in claim 2 which further comprises an evacuation groove in said stem portion facing said collar and extending upwardly beyond the plane of said collar.

6. The combination as set forth in claim 5 wherein said groove is helically disposed on said stem portion.

7. The combination as set forth in claim 1 wherein said cover protrudes into said rotor at said open end and said means includes a radial flange on said rotor about said open end in the plane of said cover.

8. The combination as set forth in claim 7 which further comprises a plurality of upstanding blades on said radial flange in the plane of said cover.

9. The combination as set forth in claim 1 wherein said cover protrudes into said rotor at said open end and said means includes a plurality of blades on the exterior of said rotor within the plane of said cover.

10. The combination as set forth in claim 3 which further comprises an evacuation groove in said stem portion facing said collar and extending upwardly beyond the plane of said collar.

11. The combination as set forth in claim 1 where said means includes a stem portion on said cover projecting into the plane of said rotor in spaced relation therewith and a helical groove in said stem portion defining said path for the evacuation of air.

12. The combination as set forth in claim 1 wherein said cover includes a stem portion projecting into the plane of said rotor and said means includes a helical rib on said stern portion in facing relation to said rotor to act as a guide blade to evacuate air from the rotor.

13. The combination as set forth in claim 1 wherein said means includes a plurality of blades on said rotor for creating a suction force to draw air from within the rotor during rotation of said rotor, said blades being mounted on the exterior of said rotor.

14. The combination of a rotor of an open end spinning device having an open end and an internal fiber collecting surface, a cover over said open end of said rotor, said cover being spaced from said rotor to define a flow path therebetween for the evacuation of air from within said rotor, and means for evacuating said fiber collecting surface disposed in said flow path to evacuate air from within said rotor through said means and through said path between said rotor and said cover into a space surrounding said rotor. 

1. The combination of a rotor of an open end spinning device having an open end on the side facing a fiber feed point and an internal fiber collecting surface, a cover over said open end of said rotor, and means for evacuating said fiber collecting surface, said means being mounted on one of said rotor and said cover and spaced from said fiber collecting surface and a fiber feed path between said feed point and said fiber collecting surface to evacuate air from within said rotor through a path between said rotor and said cover into a space surrounding said rotor.
 2. The combination as set forth in clam 1 wherein said means includes a collar on said rotor about said open end extending upwardly therefrom, and a stem portion on said cover projecting into said collar in spaced relation thereto to define an annular clearance.
 3. The combination as set forth in claim 2 wherein said stem portion has a conical wall thereon and said collar has a complementary conical wall thereon in facing relation to said stem portion.
 4. The combination as set forth in claim 3 wherein said cover is adjustably mounted axially of said rotor to vary the clearance between said stem portion and said collar.
 5. The combination as set forth in claim 2 which further comprises an evacuation groove in said stem portion facing said collar and extending upwardly beyond the plane of said collar.
 6. The combination as set forth in claim 5 wherein said groove is helically disposed on said stem portion.
 7. The combination as set forth in claim 1 wherein said cover protrudes into said rotor at said open end and said means includes a radial flange on said rotor about said open end in the plane of said cover.
 8. The combination as set forth in claim 7 which further comprises a plurality of upstanding blades on said radial flange in the plane of said cover.
 9. The combination as set forth in claim 1 wherein said cover protrudes into said rotor at said open end and said means includes a plurality of blades on the exterior of said rotor within the plane of said cover.
 10. The combination as set forth in claim 3 which further comprises an evacuation groove in said stem portion facing said collar and extending upwardly beyond the plane of said collar.
 11. The combination as set forth in claim 1 where said means includes a stem portion on said cover projecting into the plane of said rotor in spaced relation therewith and a helical groove in said stem portion defining said path for the evacuation of air.
 12. The combination as set forth in claim 1 wherein said cover includes a stem portion projecting into the plane of said rotor and said means includes a helical rib on said stem portion in facing relation to said rotor to act as a guide blade to evacuate air from the rotor.
 13. The combination as set forth in claim 1 wherein said means includes a plurality of blades on said rotor for creating a suction force to draw air from within the rotor during rotation of said rotor, said blades being mounted on the exterior of said rotor.
 14. The combination of a rotor of an open end spinning device having an open end and an internal fiber collecting surface, a cover over said open end of said rotor, said cover being spaced from said rotor to define a flow path therebetween for the evacuation of air from within said rotor, and means for evacuating said fiber collecting surface disposed in said flow path to evacuate air from within said rotor through said means and through said path between said rotor and said cover into a space surrounding said rotor. 